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      <title>项目的系统的架构是什么样的？ - 交互式测验</title>
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      </style>
    </head>
    <body>
      <div class="main-wrapper">
          <div class="quiz-container">
            <div class="quiz-header">
              <h1>项目的系统的架构是什么样的？ - 交互式测验</h1>
              <p>检验你对文档内容的理解程度</p>
            </div>
            <div id="quiz-content">
                <div class="quiz-body">
                    <div class="progress-bar">
                        <div id="progress-indicator"></div>
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                    <div id="question-container">
                      <p id="question-text"></p>
                      <ul class="options-list" id="options-list"></ul>
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                    <div id="result-container"></div>
                    <div id="hint-container" class="hint-container"></div>
                </div>
                <div class="quiz-footer" id="quiz-footer">
                  <button id="prev-btn" class="nav-btn">上一题</button>
                  <button id="hint-btn" class="nav-btn" style="background-color: #ffc107; color: #333; box-shadow: 0 4px 12px rgba(255,193,7,0.3);">提示</button>
                  <button id="next-btn" class="nav-btn">下一题</button>
                </div>
            </div>
          </div>
      </div>

      <script>
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  {
    "question": "在现代系统架构中，消息中间件（如Kafka, RabbitMQ）最核心的作用是什么？",
    "options": [
      "存储用户会话数据，以实现快速访问和状态保持。",
      "直接处理面向用户的API请求和核心业务逻辑。",
      "用于异步处理和解耦系统组件，提升系统响应和鲁棒性。",
      "管理和编排应用容器的自动化部署、扩展和运维。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "消息中间件的核心价值在于实现系统组件间的异步通信和解耦。通过将消息放入队列，生产者服务无需等待消费者服务处理完成即可继续执行，从而提高了系统的整体性能和可用性。当某个消费者服务暂时不可用时，消息会保留在队列中，待服务恢复后继续处理，增强了系统的容错能力。",
    "source": "文档中「2. 组件组成」的「消息中间件」部分",
    "hint": "思考一下，当一个任务（如发送邮件）不需要立即完成时，系统如何处理才能不阻塞主流程？"
  },
  {
    "question": "根据文档描述，以下哪项最能准确地定义“水平扩展”（Horizontal Scaling）？",
    "options": [
      "为单个服务器增加更强大的CPU、内存或存储。",
      "将一个庞大的单体应用拆分成多个独立的服务模块。",
      "通过增加更多服务器实例来分担和处理增长的负载。",
      "为关键组件设置冗余备份，以便在发生故障时自动切换。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "水平扩展，也称为向外扩展（scale out），是指通过增加更多的机器（服务器实例）来共同分担负载。这种方式可以线性地提升系统的处理能力，是构建高可用、高并发系统的常用策略。与之相对的是垂直扩展（Vertical Scaling），即增强单个服务器的硬件性能。",
    "source": "文档中「4. 扩展性和容错性」的「扩展性」部分",
    "hint": "这个概念与增加机器的“数量”有关，而不是提升单台机器的“质量”。"
  },
  {
    "question": "文档提到了两种关键的数据加密措施以保障系统安全，它们分别应用于数据的什么状态？",
    "options": [
      "传输层加密 (TLS/SSL) 用于保护传输中的数据，存储加密 (AES) 用于保护静态存储的数据。",
      "单点登录 (SSO) 用于保护用户认证过程，多因素认证 (MFA) 用于增强账户安全性。",
      "防火墙用于保护网络边界数据，访问控制用于保护应用内部数据。",
      "哈希加密用于保护用户密码，对称加密用于保护API通信。"
    ],
    "correctAnswerIndex": 0,
    "explanation": "为了实现端到端的安全，数据在不同状态下需要不同的保护。文档明确指出，传输层加密（TLS/SSL）用于保护数据在网络中传输时的安全，防止被窃听或篡改。而存储加密（如使用AES算法）则用于保护数据在数据库或文件中静态存储时的安全，防止数据泄露。",
    "source": "文档中「5. 安全性」的「数据加密」部分",
    "hint": "考虑数据生命周期的两个主要阶段：它在网络上“移动”时和它在硬盘上“静止”时。"
  },
  {
    "question": "在“部署和运维”部分提到的CI/CD流程，其主要目标是什么？",
    "options": [
      "实时监控系统各项性能指标，并在出现异常时自动报警。",
      "通过自动化构建、测试和部署，实现快速、可靠的代码持续交付。",
      "对分散在不同服务器上的应用日志进行集中化管理和分析。",
      "通过容器化技术（如Docker）打包应用及其依赖，确保环境一致性。"
    ],
    "correctAnswerIndex": 1,
    "explanation": "CI/CD（持续集成/持续交付或持续部署）的核心目标是自动化软件的发布流程。通过自动化代码的构建、单元测试、集成测试和部署，可以显著提高开发效率，保证代码质量，并实现频繁、可靠的版本发布。",
    "source": "文档中「6. 部署和运维」的「CI/CD流程」部分",
    "hint": "这个流程旨在打通从代码提交到线上部署的整个通道，使其更加自动化和高效。"
  },
  {
    "question": "文档中，缓存（如Redis）在数据层扮演的关键角色是什么？",
    "options": [
      "作为系统唯一的数据源，存储所有结构化核心数据。",
      "处理实时数据流的分析与计算。",
      "加速数据访问，并有效减轻后端数据库的负载压力。",
      "用于持久化存储非结构化数据，如用户上传的图片或文档。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "缓存系统的主要职责是存储热点数据（即频繁访问的数据）的副本。当应用需要读取数据时，会先查询缓存。如果缓存命中，则直接返回数据，避免了对后端数据库的慢速查询。这极大地提高了数据访问速度，并降低了主数据库的压力。",
    "source": "文档中「2. 组件组成」的「数据存储」部分",
    "hint": "这个组件就像是数据库的“快速通道”或“临时储物柜”，用于存放最常用的物品。"
  },
  {
    "question": "当系统的一个关键组件发生故障时，“故障转移”（Failover）机制会如何响应？",
    "options": [
      "自动增加更多服务实例来处理增加的流量。",
      "将失败的请求重新放入消息队列，等待后续处理。",
      "自动检测故障并无缝切换到预先准备好的备用实例或服务。",
      "立即触发警报通知运维人员，等待手动干预恢复。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "故障转移是实现高可用性的核心容错策略。它通过监控系统组件的健康状况，一旦检测到主服务或实例发生故障，能够自动地、快速地将流量或任务切换到健康的备用（冗余）实例上，从而保证服务的连续性，对用户的影响降到最低。",
    "source": "文档中「4. 扩展性和容错性」的「容错性」部分",
    "hint": "这个策略的核心是“切换”到一个“备用”的组件上，以确保服务不中断。"
  },
  {
    "question": "根据文档对系统架构层次的划分，处理核心业务规则和操作的功能主要位于哪个层次？",
    "options": [
      "前端层 (Frontend Layer)",
      "数据层 (Data Layer)",
      "基础设施层 (Infrastructure Layer)",
      "应用层 (Application Layer)"
    ],
    "correctAnswerIndex": 3,
    "explanation": "应用层是系统的大脑，它负责实现具体的业务逻辑和规则。当前端层接收到用户请求后，会将其转发给应用层。应用层根据预设的业务流程进行处理，可能需要与数据层进行交互以读写数据，最终将处理结果返回。",
    "source": "文档中「1. 总体架构」的「层次结构」和「2. 组件组成」的「应用组件」部分",
    "hint": "用户界面负责“看”，数据库负责“存”，而这一层负责“思考”和“处理”。"
  }
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            const totalQuestions = quizData.length;
            const answeredCount = userAnswers.filter(a => a !== null).length;
            const wrongCount = answeredCount - correctCount;
            const skippedCount = totalQuestions - answeredCount;
            const accuracy = totalQuestions > 0 ? Math.round((correctCount / totalQuestions) * 100) : 0;
            const errorRate = totalQuestions > 0 ? Math.round((wrongCount / totalQuestions) * 100) : 0;

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                '<h2>答题报告</h2>' +
                '<div class="score-summary">' +
                '<div class="score-card">' +
                '<h3>得分</h3>' +
                '<p>' + correctCount + ' / ' + totalQuestions + '</p>' +
                '</div>' +
                '<div class="score-card">' +
                '<h3>正确率</h3>' +
                '<p>' + accuracy + '%</p>' +
                '</div>' +
                '<div class="score-card">' +
                '<h3>错误率</h3>' +
                '<p>' + errorRate + '%</p>' +
                '</div>' +
                '<div class="score-card score-details">' +
                '<table>' +
                '<tr><td>正确</td><td>' + correctCount + '</td></tr>' +
                '<tr><td>错误</td><td>' + wrongCount + '</td></tr>' +
                '<tr><td>未答</td><td>' + skippedCount + '</td></tr>' +
                '</table>' +
                '</div>' +
                '</div>' +
                '<div class="report-actions">' +
                '<button id="review-btn">回顾测验</button>' +
                '<button class="primary" onclick="location.reload()">再试一次</button>' +
                '</div>' +
                '</div>';

            let reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }
            quizContentEl.insertAdjacentHTML('beforeend', finalScoreHtml);
            document.getElementById('review-btn').addEventListener('click', reviewQuiz);
        }

        function reviewQuiz() {
            const reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }

            document.querySelector('.quiz-body').style.display = 'block';
            document.getElementById('quiz-footer').style.display = 'flex';
            
            currentQuestionIndex = 0;
            loadQuestion();
            updateNavigationButtons(); // Ensure nav buttons are correctly displayed
        }

        // Event Delegation for options
        optionsListEl.addEventListener('click', (event) => {
            if (event.target && event.target.matches('li.option-item')) {
                // Check if the question has already been answered
                if (userAnswers[currentQuestionIndex] === null) {
                    const selectedIndex = parseInt(event.target.dataset.index, 10);
                    selectOption(selectedIndex);
                }
            }
        });

        prevBtn.addEventListener('click', goToPreviousQuestion);
        nextBtn.addEventListener('click', goToNextQuestion);
        hintBtn.addEventListener('click', showHint);
        
        // 初始加载
        loadQuestion();
      </script>
    </body>
    </html>
  